Bacterial adherence to uroepithelial surfaces is a critical event in the pathogenesis of urinary tract infections. This proposal will examine the antigenic and functional properties of uropathogenic E. coli adhesin proteins. The linear antigenic structure of Gal-Gal and MS pili and of the afimbrial adhesin AFA-I will be determined with synthetic peptides corresponding to regions of these sequences. Peptides specifying common, clonal and type specific epitopes will be prepared as vaccines and their efficacies determined in the BALB/c mouse model of human pyelonephritis. Synthetic peptides will be prepared that correspond to the pap E, F and G cistrons of the Gal-Gal pilus operon which do not encode the pilus subunit polypeptide, but are required for binding spedificity. Antibodies to these peptides will be used to determine the location of these gene products on the bacterial surface and with respect to the pilus filament, their role in specific adherence and to facilitate their purification by affinity chromatography. These peptides will also be tested for efficacy in the BALB/c mouse pyelonephritis model. Therefore, a library of adhesin proteins, synthetic adhesin peptides and antipeptide antibodies will be prepared in order to identify "antigenic," "immunogenic" and "protective" epitopes of E. coli adhesin proteins and to characterize the immune response in the serum and in the urine of vaccinated animals. If successful, these studies may identify useful adhesin proteins and peptides for the immunoprophylaxis of urinary tract infections in humans. Footnote: 1. Throughout this proposal, the term "immunogenic epitope" refers to a particular domain in the native protein that is recognized by the immune system and gives rise to antibodies able to bind synthetic peptides corresponding to this domain. "Antigenic epitope" is used to describe domains that are recognized in the native protein by antibodies engendered by synthetic peptides corresponding to that region of the protein. "Protective epitope" designates a linear domain of the native protein that confers protection in the murine pyelonephritis model when administered as a synthetic peptide vaccine.